Knowing that the common core state standards will require more rigor and standardized testing will require the same, my question has been...

What is developmentally appropriate? My question is especially focused on the students in grades K through 2. Therefore, I have been referring back to Chip Wood's bookYardsticks:Children in theClassroomAges 4-14.
There is a website through which you can gain more background on this book which features the development of children aged 4 through 14 and how it relates to the classroom.
Here is the link. http://www.yardsticks4-14.com